Resource Ecology & Fisheries Management (REFM) Division
Age & Growth Program
Estimated production figures for 1 January
through 31 December 2007. |
Species |
Specimens Aged |
Giant grenadier |
359 |
Greenland turbot |
502 |
Flathead sole |
1,373 |
Alaska plaice |
449 |
Dover sole |
447 |
Northern rock sole |
1,241 |
Yellowfin sole |
496 |
Arrowtooth flounder |
738 |
Bering flounder |
258 |
Walleye pollock |
12,558 |
Pacific cod |
4,999 |
Sablefish |
2,366 |
Atka mackerel |
1,629 |
Pacific ocean perch |
2,316 |
Northern rockfish |
929 |
Rougheye rockfish |
1,502 |
Shortraker rockfish |
1,052 |
Dusky rockfish |
314 |
Blackspotted rockfish |
390 |
Warty sculpin |
185 |
Yellow Irish lord |
513 |
Total production figures were 34,616 with
9,696 test ages and 347 examined and
determined to be unageable. This is the
second highest yearly production total since 1990. |
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Shark Ageing Research
The Age & Growth Program and Professor Vince Gallucci (University of Washington) began an informal collaboration on the ageing of salmon sharks (Lamna ditropis) and Pacific sleeper sharks (Somniosus pacificus). The Age and Growth Program has not previously aged sharks.
Some shark species are especially difficult to age due to their minimal amounts of skeletal calcification. The salmon shark shares the same genus as the porbeagle shark (L. nasus) which has validated ages, so the salmon shark is believed to be ageable. The Pacific sleeper shark, which shares the same genus with the Greenland shark (S. microcephalus), presents a more difficult challenge.
Researchers of the Greenland shark think this species grows to be quite old, so the Pacific sleeper shark may be similar. The problem is that the Pacific sleeper shark and Greenland shark show very little calcification, so age determination is very difficult. If you have had success ageing these species or know of any successful ageing studies please let us know!
By Dan Kimura
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